Who invented origami item?

No one really knows. Cai Lun is officially recognized in Chinese records as the creator of paper, but samples have been found as old as the 2nd-century BCE, which of course predates his existence by at least 100 years. People have a natural inclination to fold paper when they have access to it, so origami was probably developed by numerous individuals over many centuries, as opposed to a single person creating it.